The present invention relates to a display device, and particularly to a thin and light-weight flexible sheet-like display device.
In these years, with the advance of a ubiquitous network, a high-performance personal data assistance has been desired so that an advanced communication is performed in a bidirectional transmission. Such personal data assistance has an image display device on which not only text information is displayed conventionally, but also photographic images and moving images are displayed clearly. The personal data assistance further requires the following requirements such that “it should be thin and light in weight to be carried easily” “it should have a flexibility not to be fragile even if it is subject to mechanical shock in carrying around” and “it should also be low power consumption because of operation by a battery.” Further, the digital terrestrial broadcasting has been started to thereby put moving images on the image display device in vehicles such as a train, bus, automobile, etc. so that such demands are predicted to increase in the future. For this reason, it is desirable that the image display device has a thin type capable of installing on a little mounting space and also has a flexibility capable of installing on a curved surface alongside of a wall.
In the past, a liquid-crystal display has been used mainly as being corresponded to the thin-type image display device. However, the liquid-crystal display is heavy and no flexibility because the most of this type of the display uses a glass for a substrate. For this reason, the liquid-crystal display is fragile against a mechanical shock and difficult to install on the curved surface.
In order to overcome a drawback of the foregoing device, an electronic paper has been studied by utilizing an organic EL (electroluminescence), a cataphoresis of particles, etc., as a new thin-type image display device.
According to the foregoing study, there has been a paper, by Midori Kato and Masayoshi Ishibashi, “New Polymer-Actuators Using Carbon Nano-particle Composite (II)” 23rd Annual Conference of the Robotics Society of Japan, 2005, 1A32.